This is about big, long-haul airliners that are converted to private jets and can carry not only pampered passengers and their entourages, but also, in some cases, their Rolls Royces and racehorses. These are specially equipped, privately owned jumbo jets — the kind that normally carry as many 300 to 400 passengers — but reconfigured with interiors designed for the enjoyment of, at most, a couple of dozen.